let's go to randall pinkston. >> nails, bibis, small pieces of mettlal designed to create -- metal designed to create maximum damage when they exploded. >> reporter: the area around the finish line is what police call the most complex crime scene in history. investigators continue to collect and process evidence including bomb fragments and cell phone videos and photos. mourners have been placing flowers at the scene. investigators denied reports that several unexploded bombs were found in the area. >> we only have two devices that aware of device and both devices were involved in the incident. >> reporter: three people were killed and more than 175 others were injured in the two blasts. among the fatalities, 8-year- old martin richard, the boy ice sister and mother were badly injured. >> they are a wonderful family and this is a horrific tragedy. >> reporter: investigators say the 12 block area near the finish line will remain a crime scene for at least two more days. the fbi a agent in charge would not confirm reports agents are questioning a saudi national who was injured in the blast. p

mother of the two men who cbs reporter randall pinkston says is speaking in their defense. >> reporter: several streets around the boston marathon bombings site are re-op residents and businesses today's. sources tell cbs news 19-year- old marathon bombing suspect johar tsarnaev is telling investigators his older brother's radical views drove the attacks and that they were not connected to a terrorist organization. due to a gunshot injury to his throat he is only able to speak one word at a time and has been communicating with interrogators mostly in writing. in a new interview from russia today, the suspect's mother says her sons would never be involved in a terror attack. >> what happened is a terrible thing. but i know that my kids have nothing to do with this. >> reporter: the official number of injured from the bombings has jumped from an initial estimate of 170 to more than 280. boston public health officials say that's because people have been going to hospitals with injuries they did not seek treatment for the day of the

randall pinkston has more. >> reporter: investigators say they are combing through hours of video frame by frame looking for the person who planted the explosive devices. the area around the finish line of the boston marathon is what police call the complex crime scene in the city's history. >> any time bombs are used to target innocent civilians, it's an act of terror. >> reporter: investigators continue to collect and process evidence including bomb fragments and cell phone videos and photos. mourners are placing flowers at the scene. investigators denied reports that several unexploded bombs were found in the area. >> we have two devices that we are aware of. both of them did the damage and were involved in the explosive incident. >> reporter: three people were killed and more than 175 others were injured in the two blasts. among the fatalities, 8-year- old martin richard who greeted his father at the finish line. the boy's sister and mother were badly injured. >> they are a wonderful family. >> reporter: investigators say the 12 block area near the finish line will remain a crime sc

randall pinkston tells us the investigation is only just beginning. >> reporter: the fertilizer plant rocked by a massive explosion on wednesday. the blast leveled the building and destroyed surrounding structures. brian anderson and his son were sitting in his pickup truck in between buildings that no longer exist. >> god wants me here for a reason. i just gotta find out what that is now. >> reporter: rescue crews checked for anyone still trapped in the debris. the human toll is still unknown. >> there are firefighters now. >> reporter: some of the firefighters responding to the initial blaze are still missing. and they are feared dead. >> they were in very close proximity to the explosion. thus, we have not been able to locate those firemen yet. >> reporter: kenny harris was killed. he was off duty at the time but volunteered to help fight the fire. it's not yet clear what sparked the fire, but the company that operates the fertilizer plant has been cited for safety and violations. for residents in west, the immediate task is picking up the pieces. april's house is still standing wi

cbs reporter randall pinkston is live in boston. he has the very latest on the investigation and a possible suspect. randall. >> reporter: cbs news has learned that investigators have identified a suspect who may have been behind the bombings tow boston marathon. his face was caught on surveillance video. cbs news confirms a possible suspect has been identified in the boston marathon bombing case. a law enforcement force says the young man was identified at the surveillance video at the second blast seen on a cell phone at the same time the first bomb exploded. sources say investigators zeroed in on the suspect after checking cell phone records in the area at that exact time. fbi photos from the boston marathon bombing investigation show the remains of an explosive device including twisted pieces of metal charred wires and a battery. one photo shows a half inch nail and part of a zipper stained with blood. the items are now being analyzed at fbi headquarters in virginia. >> there, specialized examiners will reconstruct the device or

reporting live in west, texas, i'm randall pinkston. ck to you. >> randall, i'm sure they are anticipating citations of some kind against this company, the owner of this plant. >> reporter: we don't know they are going to do with respect to this current situation. we do know in the past owners of the plant have been cited for violations for failing to have a risk management plan, for safety violations. in fact, one of those violations was just settled last summer. >> all right. randall pinkston in west, texas, thank you. >>> we are getting our first look at the potential suspects in the boston marathon bombings. the fbi released photos and surveillance video of the two men earlier today. they are homing someone recognizes them. they were seen carrying backpacks near the finish line shortly before the explosion. >> today we are enlisting the public's help to identify the suspects. they are suspect one and suspect two. they appear to be associated. as you can see from one of the images, suspects one and two appear to be walking together th

stanford alum and nba player jason collins has come out and cbs reporter randall pinkston has more on his decision. jason collins wrote a first person account of his sexuality in the latest edition of "sports illustrated." the veteran basketball player begins the article saying, quote, i am a 34-year-old nba center. i am black. and i am gay. it is the first time an active player in the nba, nhl, major league baseball or the national football league has openly admitted being gay. collin say, quote, if i had my way, someone else would have already done this. nobody has. which is why i am raising my hand. nba commissioner david stern issued a statement on behalf of the league. he called collins a widely- respected player and said, we are proud he has assumed the leadership mantle on this very important issue. collin has played with stanford in the final four, before moving on to the nba. as mostly a backup center, he played for six teams over a dozen years including the celtics and the nets. last season, he was on the washington wizards. but he is a free agent for next year. collin says

reporting live in boston, i'm randall pinkston. back to you. >> thank you, randall. >>> washington, d.c. along with other u.s. cities have increased their security after yesterday's attack. part of new york's laguardia airport has been evacuated due to a report of a suspicious package. here locally, d.c. police have increased their patrols along today's emancipation day parade. our bruce johnson is standing by. he's in northwest washington. he has more information on that part of the story. bruce? >> reporter: jc, we're in the middle of pennsylvania avenue northwest. talked to the mayor a short time ago. he says there have been no incidents. he's excited about the size of this crowd. it's emancipation day in d.c. recognizing, commemorating what happened here back in 1862, some 3,000 slaves, african- americans were freed by abraham lincoln. that was before the emancipation proclamation. behind me a group of distinguished men. talk to me first about boston and this being the nation's capital, you know this could also be a target. what

randall pinkston, cbs news, boston. >>> a startling discovery in new york city. part of a hijacked plane used in the 9/11 attacks. it happens to be part of the landing gear. work crews found this wedged between two buildings near ground zero just 18 inches apart. one of the buildings is the site of a drawnout battle over a new islamic community center, and because of that police are exploring the possibility, however slight, that is may have been planted there. >>> developing news from oakland now. one person was killed, two injured in a shooting near children's hospital last night. that happened just a block away from where a mother was shot and killed on wednesday as her 4-year-old boy watched. in the latest shooting, witnesses say they heard up to 20 gunshots. one of the injured victims is in critical condition and another suffered non life- threatening wounds. no one has been arrested in the shooting of the mother or in last night's incidents. >>> other headlines around the bay, contra costa county will hold a prescription drug takeback today. that starts at

randall pinkston, cbs news, west texas. >>> a texas man who survived the boston bombings found himself on shaking grounds two days later. joe ran the boston marathon on monday, his wife was heading to the finish line to find him when the first bomb went off yards away from both of them. now both escaped uninjured, though his wife was hit by some shrapnel. when back in texas, joe was driving home from work last night near waco when he snapped this photo of black smoke up ahead. then he felt the explosion. he feels lucky to be alive. >>> many of the first responders to the plant explosion were volunteer firefighters. len ramirez on the need right here in the bay area for the same support. >> these are members of the spring valley volunteer fire department's first ever training academy, going through their final exams. >> these guys put their heart and souls into being a volunteer. i mean, it's not just like a hobby, it's something they are dedicated to. >> the east jose foothills is made up of 40 neighbors and people in the community who have different day jobs. >> my job is the outback